I have searched around ballyvennaght, and found what i guess was the best match for one of the other tombs, judging by the map references I could find. Pictures here http://www.flickr.com/photos/minipixel/226352662/in/set-72157594249667235/ - theres a link to its position on a map towards the botton-right of that page.

To be honest its difficult to tell whether or not its just a large erratic boulder, as it is still sunk in the bog, as i suppose the dual tombs nearby once were. I could make out other stones below, but can't be certain, which is why I didn't post here. There are a few other large schist boulders dotted about nearby in the peat-cuttings.

btw, this one is a lot easier to get to than Cloughananca No.1, lying just to the west of a (pretty rough) track, marked on the OS map. I haven't yet looked for the other tomb further north.

As for Craigs Court Tomb, If you set off with the passage tomb on your left, Its the next lane on the right up the road, once up on the hillside, you should spot the tomb on your right easily enough.